1. Technical Field
The present invention relates generally to client-server processing and, more particularly, to an application environment wherein application logic and business rules reside on a server to which users attach from client machines that have independent graphical user interface (GUI) processing.
2. Description of the Related Art
The computer industry has changed dramatically over the past few years and that, coupled with the explosive growth of the Internet, has changed the way people interact with and access information. The growth of the Graphical User Interface (GUI) and the World Wide Web, the graphical side of the Internet, has changed users' expectations of how they interact with information.
These changes present new challenges in data processing. While data processing has traditionally been performed internally, e.g., within a company site, the new global information access infrastructure allows remote data processing.
Current remote control systems that can be adapted for remote data processing such as PCAnywhere or Citrix Servers have two significant drawbacks. First, their system overhead requirements keep them from being scaled to a large number of users. Second, keyboard interaction takes place essentially on a character-by-character basis. In tests of remote control systems, and character-based systems such as Unix telnet, the character-by-character method was found unacceptable over the Internet for sustained usage of the program. With delay times typically of ¼ to ½ of a second, and sometimes more, it becomes very difficult for data entry personnel to develop any rhythm that allows for high-speed entry. Using ActiveX controls and other methods based on standard Remote Procedure Call (RPC) implementations requires too much bandwidth to perform acceptably over limited speed connections such as a 28.8 kbps connection. Moreover, additional installation is needed on the client side. Web browser based implementations do not have interactive field-by-field validation, lookups, or help needed for large-scale applications. In addition, they do not allow multiple overlapping windows.
Some operating systems (such as the Windows operating system) use an event queue to process and sequence events (such as key strokes, mouse clicks, etc.). Generally, events such as keystrokes are simply delivered to the window that is currently active. This, however, becomes somewhat complicated if a keystroke is able to activate another window. As fast users often type ahead, there is no assurance that keystrokes will be sent to the intended window.